From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The cause and resolution of 'jagger' issues in Bentley 25/30 HP clutches.
| Identifier | ExFiles\Box 129\3\ scan0210 | |
| Date | 15th May 1936 | |
| To By.{R.W. Bailey - Chief Engineer} & Mx.{John H Maddocks - Chief Proving Officer} X7110 Hs{Lord Ernest Hives - Chair}/Smth.6/KW.15.5.36. Jaggers on Bentley & 25/30 HP. Clutches. We have had one or two cases of jagger with Borg & Beck clutches on the Bentley, which have only been cured by replacing the clutch. We have examined two of the faulty clutches and have found the trouble to be due to out of parallelism of the pressure plate and flywheel when the former is withdrawn. This amounted to .008" in the case of the trials car B-2-GA, and .015" in the case of one of the test chassis. The trouble was due to the fact that all three operating fingers did not contact the trunnion thrust face simultaneously. Borg & Beck claim to set the fingers correct to .010" (i.e. .002" at the pressure plate) before pinning up the eyebolts and nuts which locate them, but on examining their rig we find that they are not able to maintain this limit in practice. We have accordingly got them to make special arrangements whereby the fingers will be set to .005" in the future, which means that the pressure plate will not be more than .001" out of truth. Hs{Lord Ernest Hives - Chair}/Smth. | ||